A magnification loupe carried by spectacles has a Galilean lens system comprising a single-element eyepiece lens and a two-element objective lens. The loupes may be mounted to eyeglass frames by a flip-up mounting member, or they may be mounted through the eyeglass lenses of the spectacles. The loupes provide high magnification while minimizing weight to thereby reduce strain and discomfort to users. In an exemplary embodiment, the objective lens has a non-circular shape that provides a wide field of view while further minimizing the weight of the loupe. A correction lens may be interchangeably coupled to the loupe housing to permit selective replacement with another correction lens to vary the working distance of the loupe.